Loader apparatus with crowd capability



Jan. 27, 1970 T. o. DAVIDSON 3,491,906

LOADER APPARATUS WITH CROWD CAPABILITY Filed Sept. 5, 1967 6 Sheets-s lINVENTOR TREVOR o. DAVIDSON ATTORNEY Jan. 27, 1970 T, o. DAVIDSON LOADERAPPARATUS WITH CROWD CAPABILITY Filed Sept. 5. 196'? 6 Sheets-Sheet 2ETn IN VENTCR TREVOR O. DAVIDSON BY A 49% ATTORN EY Jan. 27, 1.970 T, o.DAVIDSON 3,491,906

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LOADER APPARATUS WITH CROWD CAPABILITY Filed Sept. 5, 1967 6Sheets-Sheet 4 INVEN TOR I TREVOR O. DAVIDSON wzw ATTORNEY Jan. 27,11970 T, o. DAVIDSON 3,491,906

LOADER APPARATUS WITH CROWD CAPABILITY Filed Sept. 5, 196'? v 6Sheets-Sheet 5 INVENTOR TREVOR O. DAVIDSON ATTORNEY Jan. 27, 11970 T, o.DAVIDSON BOADER APPARATUS WITH CROWD CAPABILITY Fi'l-ed Sept. 5., 1967 6Sheets-Sheet 6 INVENTOR TREVOR o. DAVIDSON ATTORNEY United States Patent3,491,906 LOADER APPARATUS WITH CROWD CAPABILITY Trevor 0. Davidson,Milwaukee, Wis., assignor to Bucyrus-Erie Company, Milwaukee, Wis., acorporation of Delaware Filed Sept. 5, 1967, Ser. No. 665,334 Int. Cl.ROM? 3/ 62, 3/42 US. Cl. 214--77l) 24 Claims ABSTRACT OF THE DISCLOSUREBackground of the invention The present invention was created for afront-end loader with a crowd action capability in the operatingmechanism for crowding the bucket horizontally without moving thetractor. For years, the front-end loader has consisted essentially of abucket of some sort mounted on hydraulically actuated arms extendingfrom the chassis of a vehicle, and the movement of the vehicle wasrelied upon for the horizontal, or crowd, movement of the bucket and thearms provided the lift, or hoist, of the bucket. This type of excavatorhas begun to supplant the conventional power shovel with its dipper inmany applications, and this has given rise to demands for in creasingbucket capacity and decreasing cycling time. The magnification of themachinery necessary to accomplish the increased capacity has made itimpractical as well as awkward and slow to move the entire machine.Hence, in many instances the bucket operating mechanism has beenmodified to provide a crowd or horizontal com ponent to the bucketmovement along with the usual hoist or vertical component.

The crowd component is commonly accomplished by pivoting the bucket armon the end of a crowd arm, which is pivotally mounted on the revolvingframe of the machine. A hydraulic cylinder mounted on the revolvingframe pivots the crowd arm about its mounting on the revolving frame topropel the bucket outwardly and to retract it. The arrangements forhoisting the bucket, however, have produced a greater variation. Mostoften, a hydraulic cylinder is end-mounted between the crowd arm and thelift arm. Alternately, the hoist cylinder is mounted between therevolving frame and the lift arm. In at least two instances the cablehoist from the old dipper shovels has been adapted to hoist the bucket.A departure from these more conventional crowd and hoist mechanisms isshown in US. Patent No. 2,795,342 where a pantograph type of movement isemployed to crowd the bucket of a loading shovel mounted on a shuttlecar.

Summary of the invention The present invention relates to a loaderapparatus with crowd capability in which a lift arm having a materialhandling implement on one end has its opposite end pivotally mounted tomove with a swinging quadrilateral that swings in a plane relative to amain supporting frame; the swinging quadrilateral having the anteriormember 3,491,906 Patented Jan. 27, 1970 pivoted to the main supportingframe, a posterior men1- ber pivoted to the main supporting frame behindsaid anterior member, and a floating frame pivotally connected to saidanterior and posterior members. Crowd motion of the material handlingimplement may be provided by a crowd mechanism mounted to swing theanterior and posterior members of the swinging quadrilateral. Hoistmotion may be imparted to said material handling implement by a hoistmechanism which pivots said lift arm. A tilt mechanism controls theattitude of the material handling implement.

The structure thus set forth provides maximum crowd reach and hoist forthe material handling implement, and is readily adaptable to machineshaving a broad range of size and capacity. This invention provides thesame length of crowd motion for all hoist levels of the materialhandling implement. These capabilities make possible a large capacityfront-end loader that is relatively simple to operate, is highlymaneuverable, very versatile and it has short cycling time. Due to thelong reach of the front-end loader embodying the present invention atany bucket hoist level, such a front-end loader normally performsdigging and dumping operations which hitherto were impossible, or verytime consuming and difficult.

Brief description of the drawings FIG. 1 is a side elevation of a firstpreferred embodiment of the present invention.

FIG. 2 is a side elevation of the embodiment shown in FIG. 1 with thebucket partially extended at ground level.

FIG. 3 is a side elevation of the embodiment shown in FIG. 1 with thebucket extended and hoisted.

FIG. 4 is a side elevation of a second preferred embodiment of thepresent invention.

FIG. 5 is a side elevation of a third preferred embodiment of thepresent invention with the bucket in the retracted, ground levelposition.

FIG. 6 is a side elevation of the third embodiment shown in FIG. 5 withthe bucket extended at ground level.

FIG. 7 is a side elevation of the embodiment shown in FIG. 5 with thebucket extended and hoisted.

FIG. 8 is a side elevation of a fourth embodiment of the presentinvention.

Description of the preferred embodiments All four embodiments are shownin a front-end loader in which a scoop bucket 1 type of materialhandling implement has a capacity of about 4-8 cubic yards. The mainsupporting frame in each of the embodiments is a revolving frame 2 whichis rotatably mounted by a swing mechanism 3 on a crawler type runninggear 4. A cab 5 is mounted on the revolving frame 2 to house the usualmachinery, circuitry and controls, which typically consist of aninternal combustion engine with associated heat exchangers, mechanicallinkages, transmissions and the like, driving hydraulic pumps with theirassociated reservoirs, conduits and valves, and at the very front is thehousing for the operator and his necessary controls.

For the sake of brevity and clarity, it is helpful to describe similarstructures of the four embodiments simultaneously. Since the third andfourth embodiments are nearly identical, in this description to followthe same reference numerals will be applied to them, so that threereference numerals for equivalent structures will appear after eachelement. In each embodiment, the bucket 1 is pivotally mounted on theanterior end of a lift arm 6, 7 and 8, respectively, and each lift arm6, 7 and 8 has its posterior end pivotally connected to the upperanterior corner of a swinging quadrilateral 9, 10 and 11, which swingsthrough a vertical are normal to the revolving frame 2. Crowd motion isimparted to the bucket 1 by a crowd mechanism that is anchored to therevolving frame 2 and that swings the swinging quadrilateral 9, and 11anteriorly and posteriorly, although a crowd mechanism, such as ahydraulic cylinder mounted diagonally across the swinging quadrilateral9, 10 and 11 between any two members will operate to the same effect.The vertical movement of the bucket 1 is effected with a hoist mechanismthat is anchored to a floating frame 12, 13 and 14, which provides thetop side of the swinging quadrilateral 9, 10 and 11, respectively, andthe hoist mechanism actuates the respective lift arm 6, 7 and 8 to raiseand lower it about its pivotal connection to the swinging quadrilateral9, 10, 11. Finally, a tilt mechanism is provided to control the attitudeof the bucket 1 on the end of the lift arm 6, 7 and 8.

In the first embodiment, as in the other embodiments, the swingingquadrilateral 9 is made up of an anterior member 15 and a posteriormember 16 pivotally mounted in tandem on the revolving frame 2 so as toswing in a vertical, fore and aft arc. Hence, the revolving frame 2provides the third side of the swinging quadrilateral 9 and the floatingframe 12 is the fourth side. The anterior member 15 of the swingingquadrilateral 9 is a crowd arm 15 made up of two parallel membersmounted on the end of the torque tube 17 on either side of the cab 5,the torque tube 17 being mounted in the front end of the revolving frame2. The lift arm 6, which has the bucket 1 pivotally mounted on itsanterior end, has its posterior end pivotally connected to the top endof the crowd arm 15 at a hinge joint 18. In all the embodiments the liftarm may be pivoted on the floating frame or on the crowd arm near thepivotal connection of the crowd arm to the floating frame.

The floating frame 12 in the first embodiment is a triangular frameworkof tubular structural members joined at the apexes by corner pieces. Aposterior corner piece 19 is pivotally connected to the top end of theguide link 16, and an anterior corner piece 20 is pivotally connected tothe top end of the crowd arm 15 at the hinge joint 18 to link togetherthe anterior and posterior members 15 and 16 of the swingingquadrilateral 9. The third apex of the floating frame 12 projectsinteriorly of the swinging quadrilateral 9, and the interior cornerpiece 21 forms a mounting to anchor the one end of an hydraulic cylinder22, which serves as the hoist mechanism in this embodiment. The otherend of the hydraulic hoist cylinder 22 is pivotally fastened to the liftarm 6 intermediate its ends. The anterior corner piece 20 forms a buckettilt lever 23 that projects upwardly from the hinge joint 18, and a tiltlink 24 connects the top of the bucket tilt lever 23 to the blind end ofa hydraulic tilt cylinder 25, the piston rod end of which is connectedto the bucket 1. An L-shaped support arm 26 has one end pivotallymounted on the lift arm 6 and the other end is connected to the junctionof the tilt link 24 with the blind end of the hydraulic tilt cylinder25, completing the tilt mechanism for the bucket 1.

The posterior member, or guide link 16, has bottom ends pivotallymounted on a bracket 27 on the revolving frame 2. Note that in thisembodimentas well as in all of the other embodiments disclosed here-theposterior member, or guide link 16 is shorter than the anterior member,or crowd arm 15 of the swinging quadrilateral 9. This relationship ofthe lengths of the posterior member 16 and the anterior member 15 of theswinging quadrilateral 9 minimizes erratic movements of the bucket 1, asit is crowded forwardly by the action of the swinging quadrilateral 9 sothat little or no operator adjustment is required for a level floorcutting operation of the bucket 1.

The crowd mechanism in the first embodiment consists of a hydrauliccrowd cylinder 28, in conjunction with its connections to the otherstructure. The crowd cylinder 28 has one end pivotally mounted to abracket 29 projecting from the revolving frame 2 and its other endconnected to a bracket 30 on the posterior edge of the crowd arm 15. Thehydraulic crowd cylinder 28 may be said to be end-mounted between therevolving frame 2 and the crowd arm 15.

FIGS. 1-3 illustrate the first embodiment of the invention inrepresentative position throughout its operating cycle. In FIG. 1 thebucket 1 is at the beginning of its level floor, crowd movement, and thecrowd cylinder 28 and the hoist cylinder 22 are completely retracted. Toeffect a horizontal cut at ground level, the hoist cylinder 22 isretained in its retracted position and the crowd cylinder 28 is extendedshoving the bucket 1 forward along the floor level to the position shownin FIG. 2, and the tilt cylinder 25 is retained in the same partiallyextended condition throughout the horizontal, level floor strokeillustrated in FIGS. 1 and 2. The hoist cylinder 22 is extended to hoistthe bucket 1 from the position shown in FIG. 2 to the position shown inFIG. 3, and the tilt cylinder 25 is retracted to tilt the bucket 1upwardly so as to cut through the bank during the hoist movement towardthe position shown in FIG. 3.

In the second embodiment shown in FIG. 4, the swinging quadrilateral 10has its anterior member 31, or crowd arm 31, pivotally mounted on abracket 32 on top of the revolving frame 2, and its posterior member 33,or guide link 33, mounted on a pedestal 34 on the revolving frame 2behind the bracket 32 for the anterior member 31. The floating frame 13is a solid plate having an anterior corner 35 pivotally mounted on thetop of the anterior member 31 of the swinging quadrilateral 10, aposterior comer 36 pivotally connected to the top of the posteriormember 33 and a hoist mechanism supporting arm 37 projecting downwardlyto the interior of the swinging quadrilateral 10. The lift arm 7 ispivotally connected to the top of the crowd arm 31, and a hoist cylinder38 is end-mounted between the hoist support arm 37 and a bracket 39mounted on the underside of the lift arm 7. A hydraulic crowd cylinder40 is mounted to act between the revolving frame 2 and the crowd arm 31.A hydraulic tilt cylinder 41 is endmounted between a bracket 42 on topof the lift arm 7 and the bucket 1.

The second embodiment difl' ers from the first in that the entiremechanism is mounted somewhat higher being entirely above the revolvingframe 2. Also, a diiferent, solid plate type of construction isillustrated for the floating frame 13, as distinguished from the openframe employed in the first embodiment. A different mounting for theblind end of the hydraulic crowd cylinder 40 is illustrated, and thetilt mechanism omits the mechanical linkage that automatically adjuststhe bucket 1 in the first embodiment to compensate for the movement ofthe other members of the mechanism. In the second embodiment, either theoperator would have to adjust the attitude of the bucket 1, or someautomatic feedback control system would be required to actuate thehydraulic tilt cylinder 41 to adjust the attitude of the bucket 1 tomaintain desired bucket attitude at all points in the operating cycle.

The third and fourth embodiments appearing in FIGS. 5-7 and 8,respectively, are identical in all, but one, respect, hence it isconvenient to describe the two together. The swinging quadrilateral 11of the third and fourth embodiments has an arcuate crowd arm 43 :for ananterior member and a straight guide link 44 for a posterior member, thecrowd arm 43 and the guide link 44 will be pivotally mounted in tandemon the revolving frame 2 to swing in fore and aft vertical arcs. Thefloating frame 14 is an open framework having a flat base 45, the endsof which are pivotally mounted, respectively, to the top of the crowdarm 43 and the guide link 44. A hoist lever 46 projects perpendicularlyupward from the flat base 45 at its connection to the top of the crowdarm 43, and an arched top piece 47 joins the top of the hoist lever 46and the posterior end of the base 45. The lift arm 8 has the shape of aninverted, wide V, one leg of which is horizontal and has its posteriorend pivotally fastened on the end of the crowd arm 43. The other end ofthe horizontal leg 48 meets another leg 49 of the lift arm 8 at a knee50, this other leg 49 being generally vertical, and the lower end of theleg 49 terminates in a foot 51 on which the scoop bucket 1 is pivotallymounted. A hydraulic hoist cylinder 52 is end-mounted between the top ofthe hoist lever 46 of the floating frame 14 and a bracket 53 on the topof the knee 49 of the lift arm 8. A bucket tilt cylinder 54 has itspiston rod connected to the bucket 1 and its blind end suspended from asuspension arm 55 hanging from the horizontal leg 48 of the lift arm 8,and a tilt link 56 connects the blind end of the bucket tilt cylinder 54to the top member 47 of the floating frame 14 so that the bucket tiltcylinder 54 is also anchored against the floating frame 14 in its actionon the bucket 1. In the third embodiment, a hydraulic crowd cylinder 57has its blind end anchored at the pivotal mounting of the guide link 44on the revolving frame 2 and its piston rod connected to the crowd arm43, but in the fourth embodiment, a hydraulic crowd cylinder 58 has itsblind end pivotally mounted to the revolving frame 2 behind the guidelink 44 and its piston rod connected to the guide link 44. Hence, in thethird embodiment, as in the previous embodiments, the hydraulic crowdcylinder 57 swings the swinging quadrilateral 11 by pivoting the crowdarm 43 about its mounting on the revolving frame 2, but in the fourthembodiment, the hydraulic crowd cylinder 58 acts directly on the guidelink 44, and by pivoting the guide link 44 it swings the swingingquadn'lateral 11.

In the third and fourth embodiments, the swinging quadrilateral 11 iskept behind the operators compartment of the cab 5 by means of thearcuate shape of the crowd arm 43. The angled lift arm 8 with itsextended horizontal leg 48 keeps the lift arm 8 above and in front ofthe operators compartment. The inverted floating frame 14 with its hoistmechanism anchoring attachment projecting upwardly on the end of thehoist lever 46 raises the hoist mechanism above the operatorscompartment. Only the bucket tilt mechanism crosses the operatorscompartment, but it does not detrimentally obstruct the operatorsvision. Obviously, the bucket tilt mechanism could also be moved to thefront of the vertical leg 49 of the lift arm 8 by employing a systemsimilar to that shown in the second embodiment.

FIGS. 5, 6 and 7 illustrate the operating positions for the third andfourth embodiments corresponding to the operating positions of the firstembodiment as shown in FIGS. 1, 2 and 3, except that in FIG. 7 thebucket is shown tilted for high digging or partial dumping while in FIG.3 the bucket is shown in its carry position. FIG. 5 shows the swingingquadrilateral 11 swung to its extreme posterior position by the crowdcylinder 57. Thus, in FIG. 5 the bucket 1 is retracted to its posteriorposition, and since the hoist cylinder 52 and the tilt cylinder 54 areextended, the bucket 1 is at ground level and opening forwardly. Whenthe crowd cylinder 57 is extended, the hoist cylinder 52 and the tiltcylinder 54 remaining the same, the bucket 1 is crowded horizontallyforward to cut a level floor to the position shown in FIG. 6. Byretracting the hoist cylinder 52, the bucket is raised to the positionshown in FIG. 7.

If all of the possible positions of the bucket 1 were plotted in any oneof the embodiments shown, an area would be defined having the shape of adistorted parallelogram with two sides curved. The posterior arcuatelimit of the distorted parallelogram would be described by pass ing thebucket 1 through its entire hoist range with the crowd cylinder 28, 40,57 and 58 completely retracted, and the anterior arcuate limit would bedescribed by hoisting the bucket 1 with the crowd cylinder 28, 40, 57and 58 fully extended. The top and bottom of the distorted parallelogramwould be of equal length and defined by the reach of the bucket 1achieved by crowding the swinging quadrilateral 9, 10 and 11. The bucket1 can be placed anywhere within that arcuate area, and therefore it candig a level floor at any height within its hoist range and can beretracted or thrust forward at its maximum height for dumping. Suchflexibility, maneuverability and range of movement is made available infront-end loaders for the first time by the present invention.

The four embodiments described above illustrate different ways in whichthe present invention may be ap plied, either to achieve slightlydifferent results in some respects or to employ different types ofstructural materials. However, the invention is not confined to thesefour embodiments or any other embodiments not shown here but rather isset forth in the claims that follow. Also, while the invention has beendescribed in relation to its use with a bucket it can be effectivelyemployed for providing crowd capability to other material handlingimplements such as a fork lift.

Iclaim:

1. A loader apparatus comprising the combination of a main supportingframe;

a swinging quadrilateral having four members including said mainsupporting frame, an anterior member having one end pivotally mounted onsaid main supporting frame, a posterior member having one end pivotallymounted on said main supporting frame behind said anterior member and afloating frame joining said anterior and posterior members spaced fromsaid main supporting frame;

a lift arm having a material handling implement mounted on its anteriorend and having its posterior end pivotally mounted to said swingingquadrilateral;

a crowd mechanism acting between at least two members of said swingingquadrilateral to cause said posterior and anterior members to pivotabout their pivotal mountings on the main supporting frame; and

a hoist mechanism mounted between said floating frame and said lift armto pivot said lift arm about its connection to said swingingquadrilateral.

2. A loader apparatus as set forth in claim 1 wherein said swingingquadrilateral projects generally normal to said revolving frame, andsaid floating frame has a depending projection; and

said hoist mechanism is a hydraulic cylinder mounted between saiddepending projection on said floating frame and said lift arm.

3. A loader apparatus as set forth in claim 2 wherein said floatingframe is an open framework having three corners.

4. A loader apparatus as set forth in claim 2 wherein said floatingframe is a solid plate member.

5. A loader apparatus as set forth in claim 1 wherein said crowdmechanism is a hydraulic cylinder mounted between said main supportingframe and said anterior member of said swinging quadrilateral.

6. A loader apparatus as set forth in claim 1 wherein said crowdmechanism is a hydraulic cylinder mounted between said main supportingframe and said posterior member of said swinging quadrilateral.

7. A loader apparatus as set forth in claim 1 wherein said lift arm isan angled member having one leg adjacent its posterior end and anotherleg adjacent its anterior end, said legs converging together to bejoined at a knee.

8. A loader apparatus as set forth in claim 7 wherein said floatingframe has an upwardly projecting hoist lever; and

this said hoist mechanism is a hydraulic cylinder mounted between a topend of said hoist lever and said knee on said lift arm.

9. A loader apparatus as set forth in claim 8 wherein said anteriormember of said swinging quadrilateral is an arcuate shaped crowd arm.

10. A loader apparatus comprising the combination of a main supportingframe;

a swinging quadrilateral supported on and including said main supportingframe as one of its four members to swing through an are generallynormal to said main supporting frame and having an anterior member withone end pivotally mounted on said main supporting frame, a posteriormember having one end pivotally mounted on said main supporting frame intandem with said anterior member, said posterior member being shorterthan said anterior member, and a floating frame as a top member of saidswinging quadrilateral and being pivotally connected to said anteriormember and to said posterior member;

a lift arm being pivotally connected to said swinging quadrilateral andsuporting a material handling implement on its end;

a hoist mechanism including a hydraulic cylinder mounted between saidfloating frame and said lift arm for pivoting said lift arm about itspivotal connection to said swinging quadrilateral; and

a crowd mechanism acting between at least two of said four members ofsaid swinging quadrilateral to cause said posterior and anterior membersto pivot about their mountings on said main supporting frame.

11. A loader apparatus as set forth in claim 10 wherein said crowdmechanism is a hydraulic cylinder mounted between said main supportingframe and said anterior member of said swinging quadrilateral.

12. A loader apparatus as set forth in claim 10 wherein said crowd.mechanism is a hydraulic cylinder mounted between said main supportingframe and said posterior member of said swinging quadrilateral.

13. A loader apparatus as set forth in claim 10 wherein said materialhandling implement is pivotally supported on the end of said lift arm;and

a tilt mechanism is connected to said material handling implement tocontrol the attitude of said material handling implement about itspivotal connection to said lift arm.

14. A loader apparatus as set forth in claim 13 wherein said tiltmechanism includes a hydraulic cylinder connected between said lift armand said material handling implement.

15. A loader apparatus as set forth in claim 13 wherein said tiltmechanism includes a hydraulic cylinder connected between said floatingframe and said material handling implement to control the attitude ofsaid materialhandling implement.

16. A loading apparatus with crowd action capability comprising thecombination of a main supporting frame;

a crowd arm having a lower end pivotally mounted and said crowd arm toswing in unison about their respective pivotal mountings;

a hydraulic crowd actuator anchored to said supporting frame andconnected to swing said crowd arm and said guide link about theirpivotal mountings; and

a hydraulic hoist actuator connected between said floating frame andsaid lift arm to pivot said lift arm about its pivotal mounting on saidupper end of said crowd arm.

17. A loader apparatus as set forth in claim 16 wherein said guide linkis shorter than said crowd arm to guide said scoop bucket in asubstantially horizontal path when said hydraulic crowd actuator swingssaid crowd arm and said guide link.

18. A loader apparatus as set forth in claim 16 wherein a bucket tilt.mechanism is connected between said floating frame and said bucket toautomatically control the attitude of said bucket when said lift arm ispivoted by said hydraulic hoist actuator to maintain a preset attitudeof said bucket.

19. A loader apparatus as set forth in claim 16 wherein said bucket tiltmechanism includes a hydraulic cylinder connected to said bucket foroperator adjustment of said bucket attitude.

20. A loader apparatus as set forth in claim 16 wherein said hydrauliccrowd actuator is a hydraulic cylinder end-mounted between said mainframe and said crowd arm.

21. A loader apparatus as set forth in claim 16 wherein said floatingframe has a projection extending downwardly intermediate its ends; and

said hydraulic hoist actuator is a hydraulic cylinder end-mountedbetween said projection on said floating frame and an underside of saidlift arm.

22. A loader apparatus as set forth in claim 16 wherein said floatingframe has a hoist lever projecting upwardly from its anterior end; and

said hydraulic hoist actuator is a hydraulic cylinder end-mountedbetween said hoist lever on said floating frame and said lift arm.

23. A loader apparatus as set forth in claim 16 wherein said floatingframe is a solid plate structure having at least three corners, two ofsaid corners being said ends pivotally fastened to said guide link andsaid crowd arm, respectively.

24. A loader apparatus as set forth in claim 16 wherein said mainsupporting frame is a revolving frame rotatably supported by a swingmechanism on a crawler type running gear and supporting a cab forhousing an operator and a power source for said apparatus.

References Cited UNITED STATES PATENTS 2,795,342 6/1957 Steele 214783,024,933 3/1962 Albert et a1. 21477O X 3,197,049 7/1965 SchWing 214138HUGO O. SCHULZ, Primary Examiner US. Cl. X.R. 214141

